Energy-Efficient Power Amplifier Design for Advanced IoT Devices and Future Electronics

Abstract

Due to the growing popularity of the Internet of Things (IoT) and edge computing solutions, the demand on the highly energy-efficient wireless communications components (most often, on the so-called power amplifiers, or PAs) has been increasing rapidly. The use of the power and thermal management of any system is also a major bottleneck in the current IoT network because of the necessity of long life battery, compact size, and always connected networks. To overcome such issues, a paper is proposed to introduce a new architecture of Class-E power amplifier dedicated to low-power advanced IoT and edge electronic applications. This paper contains a simulation-based design approach with Cadence Spectre and ADS co-simulation strategy to assess circuit level performance and tune down the power. Its 180nm CMOS manufacturing process with adaptive gate biasing, harmonic suppression filtering, and capacitive load impedance modulation provides the proposed amplifier with an optimal platform and improved energy efficiency that does not interfere with the amplifier linearity and gain. It has an output matching network designed to be implemented to suppress the higher-order harmonics to enhance impedance matching to the 2.4 GHz ISM band that is commonly used in IoT communication standards like Bluetooth Low Energy (BLE), ZigBee, and IEEE 802.15,4. The design has a peak power added efficiency (PAE) of 68.4%, an output power of 14.2 dBm and return loss of -18.2 dB, which is more than 40 per cent better than conventional Class-A and Class-AB designs. It also consumes less than 0.35 mm 2 total silicon footprint and thus it is very appropriate to be used in system-on-chip (SoC) implementations within battery-powered smart wearables and wireless sensor nodes. The proposed design is scalable to future multi-band (compatible with emerging applications in smart cities, connected health via remote health monitoring, and the deployment of IoT devices in industrial setups, etc.) or reconfigurable PA applications in addition to its current architecture.